1. Field of the Invention
The invention relates to computer networks such as the World Wide Web and, more particularly, to the correction of information links, such as hypertext links, which point to a network document which has been relocated in information space.
2. Description of Related Art
Public data networks, such as the World Wide Web, use standard communication protocols which enable computers connected to the network to process requests for data from users. These protocols allow document authors to link their content with any other content that exists on the network. For example, if when creating a web page an author mentions the company Sun Microsystems, the author may decide to link the text "Sun Microsystems" to the company's web site. This enables anyone reading the web page to access the Sun web site just by clicking on the linked text.
Processes and techniques for comparing two electronic documents and displaying the differences between them exist in the art. For example, Microsoft.TM.'s Word.TM. 97 program contains a "track changes" feature that displays the differences between two documents highlighted in a particular way, such as using a red font.
Processes and techniques for finding and replacing text specified by a user exist in the art. This feature appears in just about every major word processing and text editing package. With this feature a user can enter one character string to be found in a document and another character string that will replace the original when it is found in the document.
Processes and techniques for encrypting data transmissions exist in the art. Public-private key encryption is one from of data encryption widely available. Public-private key cryptography is based on a mathematical process that generates two keys where one key cannot be determined from knowing the other. The private key is known only to the user. Typically it is a long series of characters stored on the user's computer. The public key is "published", that is, made available to anyone who wants it. When the user needs to send a secure transmission, the data is encrypted using his private key. When the transmission is received the recipient can decrypt the data using the corresponding public key.
The Problems
When a Webmaster or the author, owner or maintainer of an on-line document on a site receiving requests for the document (receiving site) changes the location of the document, hypertext links contained in documents on other sites (feeding or feeder sites) which point to that document, become no longer valid. This can cause a significant decrease in the number of people visiting a web page. It also leads to an excessive number of error messages to users and to a less than optimal user experience on the network.